LiDAR data (August 2008) for the Andrews Experimental Forest and Willamette National Forest study areas

Watershed Sciences, Inc. collected Light Detection and Ranging (LiDAR) data from HJ Andrews and the Willamette National Forest (WNF) on August 10-11, 2008. Total area of the study are is 17,705 acres. The total area of delivered LiDAR including 100 m buffer is 19,493 acres. This data set includes the base products delivered by Watershed Sciences, and derived products (hill shades, slope and aspect grids, and contours). The base products include the point cloud data (LAS format), and the derived bare-earth and highest-hits digital elevation models (DEM). The DEMs are at 1 meter cell size resolution. The bare-earth DEM is a representation of the topography of the area, with all the vegetation removed. The highest-hit DEM is a representation of the first object the LiDAR system struck during data capture. This includes the bare-earth topography with vegetation and structures. The vegetation DEM is the result of subtracting the bare-earth DEM from the highest-hit DEM. The elevations are the heights of the vegetation. The final products are in ESRI GRID digital format, with a 1 meter cell size resolution. Each cell in the GRID has a value that represents the modeled elevation (either total elevation or vegetation height) at that location. The resulting DEM's were used to create slope, aspect, hill shade, and contour data for the area.沃特斯赛德科学公司（Watershed Sciences, Inc.）于2008年8月10日至11日，在HJ安德鲁斯区域与威拉米特国家森林（Willamette National Forest, WNF）采集了激光雷达（Light Detection and Ranging, LiDAR）数据。本次研究区域总面积为17705英亩，包含100米缓冲区的交付激光雷达数据总面积达19493英亩。本数据集包含沃特斯赛德科学公司交付的基础产品与衍生产品：基础产品为LAS格式的点云数据，衍生产品则涵盖山体阴影栅格、坡度坡向栅格、等高线数据，以及裸地数字高程模型（Digital Elevation Model, DEM）与最高回波数字高程模型。两类数字高程模型的栅格单元分辨率均为1米。其中，裸地DEM代表去除所有植被后的区域地形；最高回波DEM代表激光雷达系统在数据采集阶段首次击中的物体表面，包含裸地地形、植被与人工构筑物。植被DEM通过将最高回波DEM减去裸地DEM计算得到，其栅格值对应植被的高度。最终产品采用ESRI GRID数字格式，栅格单元分辨率为1米，每个栅格单元的数值代表该位置的模拟高程（总高程或植被高度）。本次生成的数字高程模型还被用于制作研究区域的坡度、坡向、山体阴影及等高线数据。